Pilot-scale production of mcl-PHA by Pseudomonas citronellolis using acetic acid as the sole carbon source.

Medium-chain-length polyhydroxyalkanoates (mcl-PHA) are biobased materials with promising properties for environmentally friendly applications. Due to high production costs, which are related to the cost of the carbon sources combined with conversion insufficiencies, currently only small quantities are produced. This results in a lack of reliable data on properties and application potential for the variety of polymers from different types of production strains.

Bio-Polyester/Rubber Compounds: Fabrication, Characterization, and Biodegradation.

Biobased and biodegradable polymers (BBDs) such as poly(3-hydroxy-butyrate), PHB, and poly(3-hydroxybutyrate--3-hydroxyvalerate) (PHBV) are considered attractive alternatives to fossil-based plastic materials since they are more environmentally friendly. One major problem with these compounds is their high crystallinity and brittleness. In order to generate softer materials without using fossil-based plasticizers, the suitability of natural rubber (NR) as an impact modifier was investigated in PHBV blends.

Characterization of polyhydroxyalkanoates produced by Synechocystis salina from digestate supernatant.

The current commercial production of polyhydroxyalkanoates (PHA) is based on heterotrophic bacteria, using organic carbon sources from crops. To avoid the competition with food and feed production, cyanobacteria, metabolising PHA from carbon dioxide can be used. This research focuses on the investigation of the thermal and rheological properties of PHA polymers accumulated by Synechocystis salina, which had been cultivated in digestate supernatant and a mineral medium.

Nonspecific protein adsorption on cationically modified Lyocell fibers monitored by zeta potential measurements.

Nonspecific protein deposition on Lyocell fibers via a cationization step was explored by adsorption of two different N,N,N-trimethyl chitosan chlorides (TMCs). Both, the cationization and the subsequent protein deposition steps were performed and monitored in situ by evaluating the zeta potential using the streaming potential method. Both employed TMCs (degree of substitution with NMeCl groups: 0.

Enzymes as Biodevelopers for Nano- And Micropatterned Bicomponent Biopolymer Thin Films.

The creation of nano- and micropatterned polymer films is a crucial step for innumerous applications in science and technology. However, there are several problems associated with environmental aspects concerning the polymer synthesis itself, cross-linkers to induce the patterns as well as toxic solvents used for the preparation and even more important development of the films (e.g.

Modification Pathways for Copoly(2-oxazoline)s Enabling Their Application as Antireflective Coatings in Photolithography.

Chromophore-functionalized copoly(2-oxazoline)s are successfully evaluated as bottom antireflective coatings (BARCs) in high-resolution photolithography. With respect to UV light sources used in photolithographic production routines, anthracene is chosen as a chromophore. For application as polymer in BARCs, the copolymer poly(2-ethyl-2-oxazolin)45 -stat-poly(2-dec-9'-enyl-2-oxazolin)20 -stat-poly(2-(3'-(1"-(anthracen-9-ylmethyl)-1",2",3"-triazol-4-yl)propyl)-2-oxazolin)35 can be synthesized by the Huisgen cycloaddition click reaction of the copolymer poly(2-ethyl-2-oxazolin)45 -stat-poly(2-dec-9'-enyl-2-oxazolin)20 -stat-poly(2-pent-4'-inyl-2-oxazolin)35 and the corresponding azide-functionalized anthracenes.

The π-Electron Delocalization in 2-Oxazolines Revisited: Quantification and Comparison with Its Analogue in Esters.

The single crystal X-ray analysis of the ester-functionalized 2-oxazoline, methyl 3-(4,5-dihydrooxazol-2-yl)propanoate, revealed π-electron delocalization along the N-C-O segment in the 2-oxazoline pentacycle to significant extent, which is comparable to its counterpart along the O-C-O segment in the ester. Quantum chemical calculations based on the experimental X-ray geometry of the molecule supported the conjecture that the N-C-O segment has a delocalized electronic structure similar to an ester group. The calculated bond orders were 1.

Archaeal production of polyhydroxyalkanoate (PHA) co- and terpolyesters from biodiesel industry-derived by-products.

The archaeon Haloferax mediterranei was selected for production of PHA co- and terpolyesters using inexpensive crude glycerol phase (CGP) from biodiesel production as carbon source. CGP was assessed by comparison with the application of pure glycerol. Applying pure glycerol, a copolyester with a molar fraction of 3-hydroxybutyrate (3HB) of 0.

Poly(2-oxazoline)-derived contact biocides: contributions to the understanding of antimicrobial activity.

A set of poly(2-oxazoline)-derived (co-)polymers was prepared by microwave-assisted polymerizations and acid-mediated hydrolysis and tested for antimicrobial activity in 50 × 50 × 2 mm PP compound plates containing 5 wt% of the polymers. Antimicrobial activity against gram-negative E. coli and P.

Nonradiative deactivation of europium(III) luminescence as a detection scheme for moisture.

The nonradiative deactivation of the excited state of europium(III)-based phosphors via OH-vibrations in the presence of water allows the detection of moisture in nitrogen at concentration levels down to at least 25 ppm (0.09% RH).

One decade of microwave-assisted polymerizations: quo vadis?

The application of microwave irradiation in polymer syntheses and modifications is of continuously growing interest and has received significant international interest since the beginning of the millennium. Preceded by a review that was published 6 years ago, the present paper summarizes the most recent trends in this research area. Radical as well as step-growth and ring-opening polymerizations will be addressed; furthermore, the evolution from microwave-assisted polymerizations to microwave-assisted material fabrication will be described on the examples of polymeranalogous reactions, polymer/metal composites and bio-based materials.

cis-Dichlorido(1,3-dimesitylimidazolidin-2-yl-idene)(2-formyl-benzyl-idene-κC,O)ruthenium diethyl ether solvate.

The title compound, [RuCl(2)(C(8)H(6)O)(C(21)H(26)N(2))]·C(4)H(10)O, contains a catalytically active ruthenium carbene complex of the 'second-generation Grubbs/Hoveyda' type with Ru in a square-pyramidal coordination, the apex of which is formed by the benzyl-idene carbene atom with Ru=C 1.827 (2) Å. The complex shows the uncommon cis, rather than the usual trans, arrangement of the two chloride ligands, with Ru-Cl bond lengths of 2.

Molecular fluorescent pH-probes based on 8-hydroxyquinoline.

Three 5,7-pi-extended 8-benzyloxyquinolines, namely 5,7-diphenyl-, 5,7-bis(biphenyl-4-yl)- and 5,7-bis(4-dibenzothiophenyl)-8-benzyloxyquinoline were prepared and investigated as fluorescent pH-probes in nonaqueous solution. Absorption and photoluminescence spectra of the introduced compounds also including the starting material 8-benzyloxy-5,7-dibromoquinoline as well as their N-protonated counterparts were recorded and the results were rationalized by quantum-chemical calculations. A pronounced red shift of the emission occurred upon protonation of the non halogenated derivatives, while the dibromo-derivative is hardly emissive and is virtually not protonated under the conditions used.